Fluoxetine affords robust neuroprotection in the postischemic brain via its anti-inflammatory effect

Trazodone counteracts the response of microglial cells to inflammatory stimuli

Microglia are resident brain cells that regulate neuronal development and innate immunity. Microglia activation participates in the cellular response to neuroinflammation, thus representing a possible target for pharmacological strategies aimed to counteract the onset and progression of brain disorders, including depression. Antidepressant drugs have been reported to reduce neuroinflammation by acting also on glial cells. Herein, the potential anti-inflammatory and neuroprotective effects of trazodone (TRZ) on the microglial human microglial clone 3 (HMC3) cell line were investigated. HMC3 cells were activated by a double inflammatory stimulus (lipopolysaccharide [LPS] and tumour necrosis factor-alpha [TNF-α], 24 h each), and the induction of inflammation was demonstrated by (i) the increased expression levels of nuclear factor kappa-light-chain-enhancer of activated B cells (NF-kB) and ionized calcium-binding adapter molecule 1 (IBA-1), and (ii) the increased release of interleukin 6 (IL-6) and transforming growth factor-beta (TGF-β). TRZ effects were evaluated by treating HMC3 cells for 24 h before (pre-treatment) and after (post-treatment) the double inflammatory stimulus. Notably, TRZ treatments significantly decreased the expression of NF-kB and IBA-1 and the release of the cytokines IL-6 and TGF-β. Moreover, TRZ prevented and reduced the release of quinolinic acid (QUIN), a known neurotoxic kynurenine metabolite. Finally, cellular supernatants collected from microglial cells pre-treated LPS-TNF-α with TRZ were able to improve neuronal-like cell viability, demonstrating a potential neuroprotective effect. Overall, this study suggests the anti-inflammatory effects of TRZ on human microglia and strives for its neuroprotective properties.

The atypical antidepressant tianeptine confers neuroprotection against oxygen-glucose deprivation

Proregenerative and neuroprotective effects of antidepressants are an important topic of inquiry in neuropsychiatric research. Oxygen-glucose deprivation (OGD) mimics key aspects of ischemic injury in vitro. Here, we studied the effects of 24-h pretreatment with serotonin (5-HT), citalopram (CIT), fluoxetine (FLU), and tianeptine (TIA) on primary mouse cortical neurons subjected to transient OGD. 5-HT (50 μM) significantly enhanced neuron viability as measured by MTT assay and reduced cell death and LDH release. CIT (10 μM) and FLU (1 μM) did not increase the effects of 5-HT and neither antidepressant conferred neuroprotection in the absence of supplemental 5-HT in serum-free cell culture medium. By contrast, pre-treatment with TIA (10 μM) resulted in robust neuroprotection, even in the absence of 5-HT. Furthermore, TIA inhibited mRNA transcription of candidate genes related to cell death and hypoxia and attenuated lipid peroxidation, a hallmark of neuronal injury. Finally, deep RNA sequencing of primary neurons subjected to OGD demonstrated that OGD induces many pathways relating to cell survival, the inflammation-immune response, synaptic dysregulation and apoptosis, and that TIA pretreatment counteracted these effects of OGD. In conclusion, this study highlights the comparative strength of the 5-HT independent neuroprotective effects of TIA and identifies the molecular pathways involved.

Selenization of Small Molecule Drugs: A New Player on the Board

There is an urgent need to develop safer and more effective modalities for the treatment of a wide range of pathologies due to the increasing rates of drug resistance, undesired side effects, poor clinical outcomes, etc. Throughout the years, selenium (Se) has attracted a great deal of attention due to its important role in human health. Besides, a growing body of work has unveiled that the inclusion of Se motifs into a great number of molecules is a promising strategy for obtaining novel therapeutic agents. In the current Perspective, we have gathered the most recent literature related to the incorporation of different Se moieties into the scaffolds of a wide range of known drugs and their feasible pharmaceutical applications. In addition, we highlight different representative examples as well as provide our perspective on Se drugs and the possible future directions, promises, opportunities, and challenges of this ground-breaking area of research.

Chronic Treatment with Serotonin Selective Reuptake Inhibitors Does Not Affect Regrowth of Serotonin Axons Following Amphetamine Injury in the Mouse Forebrain

A current hypothesis to explain the limited recovery following brain and spinal cord trauma stems from the dogma that neurons in the mammalian central nervous system lack the ability to regenerate their axons after injury. Serotonin (5-HT) neurons in the adult brain are a notable exception in that they can slowly regrow their axons following chemical or mechanical lesions. This process of regrowth occurs without intervention over several months and results in anatomical recovery that approximates the preinjured state. During development, serotonin is a trophic factor, playing a role in both cell survival and axon growth. Additionally, some studies have shown that stroke patients treated after injury with serotonin selective reuptake inhibitors (SSRIs) appeared to have improved recovery. To test the hypothesis that serotonin can influence the regrowth of 5-HT axons, mice received a high dose of para-chloroamphetamine (PCA) to induce widespread retrograde degeneration of 5-HT axons. Then, after a short rest period to avoid any interaction with the acute injury phase, SSRIs were administered daily for 6 or 10 weeks. Using immunohistochemistry in 5-HT transporter-GFP BAC transgenic mice, we determined that while PCA led to a rapid initial decrease in total 5-HT axon length in the somatosensory cortex, visual cortex, or area CA1 of the hippocampus, treatment with either fluoxetine or sertraline (two different SSRIs) did not affect the recovery of axon length. These results suggest that chronic SSRI treatment does not affect the regrowth of 5-HT axons and argue against SSRIs as a potential therapy following brain injury.

Neurodevelopmental and Neuropsychiatric Disorders

This chapter will focus on microglial involvement in neurodevelopmental and neuropsychiatric disorders, particularly autism spectrum disorder (ASD), schizophrenia and major depressive disorder (MDD). We will describe the neuroimmune risk factors that contribute to the etiopathology of these disorders across the lifespan, including both in early life and adulthood. Microglia, being the resident immune cells of the central nervous system, could play a key role in triggering and determining the outcome of these disorders. This chapter will review preclinical and clinical findings where microglial morphology and function were examined in the contexts of ASD, schizophrenia and MDD. Clinical evidence points out to altered microglial morphology and reactivity, as well as increased expression of pro-inflammatory cytokines, supporting the idea that microglial abnormalities are involved in these disorders. Indeed, animal models for these disorders found altered microglial morphology and homeostatic functions which resulted in behaviours related to these disorders. Additionally, as microglia have emerged as promising therapeutic targets, we will also address in this chapter therapies involving microglial mechanisms for the treatment of neurodevelopmental and neuropsychiatric disorders.

Retrospective analysis of acute ischemic stroke shows timing of antidepressant use associated with short-term recovery and functional independence at 90-days

BACKGROUND

Little is known about how the timing of antidepressant use influences stroke outcomes. Previous research shows conflicting results on the impact of a new antidepressant prescription on stroke recovery.

OBJECTIVE

The objective of this exploratory, retrospective analysis is to examine stroke outcomes by timing of antidepressant use among patients who received stroke treatment.

METHODS

12,590 eligible patients were treated for a primary or secondary diagnosis of ischemic stroke. The outcome variables were a change in ambulation or modified Rankin scale (mRs) from pre-stroke to discharge; and a change in mRS from pre-stroke to 90-days post-discharge. The independent variable of interest was timing of antidepressant treatment. Logistic regression with generalized estimating equations was used, controlling for covariates.

RESULTS

Our model predicted that a new antidepressant prescription at discharge was associated with a ∼7% decrease in the likelihood of returning to baseline functional independence at 90-days compared to patients currently using an antidepressant (AOR:0.510, CI:0.277-0.938, p = 0.03).

CONCLUSION

These results suggest that use of antidepressants was associated with stroke recovery, but the effects are moderated by sex. Further study is needed to determine if this relationship is causal and the mechanisms between timing of antidepressant treatment and outcomes.

Integrative Approaches in Acute Ischemic Stroke: From Symptom Recognition to Future Innovations

Among the high prevalence of cerebrovascular diseases nowadays, acute ischemic stroke stands out, representing a significant worldwide health issue with important socio-economic implications. Prompt diagnosis and intervention are important milestones for the management of this multifaceted pathology, making understanding the various stroke-onset symptoms crucial. A key role in acute ischemic stroke management is emphasizing the essential role of a multi-disciplinary team, therefore, increasing the efficiency of recognition and treatment. Neuroimaging and neuroradiology have evolved dramatically over the years, with multiple approaches that provide a higher understanding of the morphological aspects as well as timely recognition of cerebral artery occlusions for effective therapy planning. Regarding the treatment matter, the pharmacological approach, particularly fibrinolytic therapy, has its merits and challenges. Endovascular thrombectomy, a game-changer in stroke management, has witnessed significant advances, with technologies like stent retrievers and aspiration catheters playing pivotal roles. For select patients, combining pharmacological and endovascular strategies offers evidence-backed benefits. The aim of our comprehensive study on acute ischemic stroke is to efficiently compare the current therapies, recognize novel possibilities from the literature, and describe the state of the art in the interdisciplinary approach to acute ischemic stroke. As we aspire for holistic patient management, the emphasis is not just on medical intervention but also on physical therapy, mental health, and community engagement. The future holds promising innovations, with artificial intelligence poised to reshape stroke diagnostics and treatments. Bridging the gap between groundbreaking research and clinical practice remains a challenge, urging continuous collaboration and research.

Mass spectrometry imaging as an emerging tool for studying metabolism in human brain organoids

Human brain organoids are emerging models to study human brain development and pathology as they recapitulate the development and characteristics of major neural cell types, and enable manipulation through an in vitro system. Over the past decade, with the advent of spatial technologies, mass spectrometry imaging (MSI) has become a prominent tool for metabolic microscopy, providing label-free, non-targeted molecular and spatial distribution information of the metabolites within tissue, including lipids. This technology has never been used for studies of brain organoids and here, we set out to develop a standardized protocol for preparation and mass spectrometry imaging of human brain organoids. We present an optimized and validated sample preparation protocol, including sample fixation, optimal embedding solution, homogenous deposition of matrices, data acquisition and processing to maximize the molecular information derived from mass spectrometry imaging. We focus on lipids in organoids, as they play critical roles during cellular and brain development. Using high spatial and mass resolution in positive- and negative-ion modes, we detected 260 lipids in the organoids. Seven of them were uniquely localized within the neurogenic niches or rosettes as confirmed by histology, suggesting their importance for neuroprogenitor proliferation. We observed a particularly striking distribution of ceramide-phosphoethanolamine CerPE 36:1; O2 which was restricted within rosettes and of phosphatidyl-ethanolamine PE 38:3, which was distributed throughout the organoid tissue but not in rosettes. This suggests that ceramide in this particular lipid species might be important for neuroprogenitor biology, while its removal may be important for terminal differentiation of their progeny. Overall, our study establishes the first optimized experimental pipeline and data processing strategy for mass spectrometry imaging of human brain organoids, allowing direct comparison of lipid signal intensities and distributions in these tissues. Further, our data shed new light on the complex processes that govern brain development by identifying specific lipid signatures that may play a role in cell fate trajectories. Mass spectrometry imaging thus has great potential in advancing our understanding of early brain development as well as disease modeling and drug discovery.

Lipopolysaccharide Preconditioning Restricts Microglial Overactivation and Alleviates Inflammation-Induced Depressive-like Behavior in Mice

Overactive microglia and severe neuroinflammation play crucial roles in the development of major depressive disorder. Preconditioning with lipopolysaccharide (LPS) provides protection against severe neuroinflammation. However, administering high doses of LPS to mice triggers depressive symptoms. Therefore, the optimal dose of LPS preconditioning needs to be determined by further experiments. LPS preconditioning is an effective agent in anti-inflammation and neuroprotection, but the mechanism by which LPS preconditioning acts in depression remain unclear. This study finds that the anti-inflammation mechanism of low-dose LPS preconditioning is mainly dependent on G-protein-coupled receptor 84 (GPR84). We use low-dose LPS for preconditioning and re-challenged mice or BV2 microglia with high-dose LPS. In addition, RNA-seq is used to explore underlying changes with LPS preconditioning. Low-dose LPS preconditioning reduces the expression of pro-inflammatory mediators and inhibits microglial activation, as well as suppresses the depressive-like behavior when the mice are re-challenged with high-dose LPS. Further investigation reveals that the tolerance-like response in microglia is dependent on the GPR84. Here, we show that low-dose LPS preconditioning can exert anti-inflammation effects and alleviates inflammation-induced depressive-like behavior in mice. As a potential therapeutic target for depression, LPS preconditioning needs to be given further attention regarding its effectiveness and safety.

Recovery in Stroke Patients Treated With Fluoxetine Versus Placebo: A Pooled Analysis of 7,165 Patients

BACKGROUND

Stroke is a major cause of disability and death. Stroke recovery outcomes range from functional impairment to disability. This study was designed to compare the recovery results of stroke patients treated with fluoxetine to those treated with placebo.

REVIEW SUMMARY

Seventeen randomized clinical trials were identified by searching PubMed, Cochrane, Scopus, and Web of Science until June 2021. Fluoxetine enhances the National Institutes of Health Stroke Scale (NIHSS) score [mean difference (MD)=-0.67, 95% confidence interval (CI) (-1.19 to -0.15)] and the Fugl-Meyer Motor Scale (FMMS) score [MD=17.36, 95% CI (12.12-22.61)] at the 3-month follow up. However, the NIHSS score showed no significant difference between the 2 groups at 2 weeks [MD=-0.32, 95% CI (-0.72 to 0.07)] or at 6 months [MD=-0.17, 95% CI (-0.47 to 0.14)]. Fluoxetine-treated and placebo-treated patients had the same overall impact on FMMS scores at 1 month ( P =0.41). Barthel index showed no significant difference between the 2 arms at 3 months ( P =0.21) or 6 months ( P =0.68). Fluoxetine-treated patients were at a higher risk of broken bone [risk ratios (RR)=2.30, 95% CI (1.59-3.32)] and hyponatremia [RR=2.12, 95% CI (1.19-3.76)], and at lower risk of new depression [RR=0.72, 95% CI (0.61-0.84)] in comparison with placebo.

CONCLUSION

The efficacy of fluoxetine on the NIHSS and FMMS is likely to take time to emerge and is expected to be transient. The Barthel index score did not differ between the fluoxetine and placebo groups. The use of fluoxetine increased the incidence of hyponatremia and bone fractures while decreasing the risk of new-onset depression.

Therapeutic treatment with fluoxetine using the chronic unpredictable stress model induces changes in neurotransmitters and circulating miRNAs in extracellular vesicles

The most widely prescribed antidepressant, fluoxetine (FLX), is known for its antioxidant and anti-inflammatory effects when administered post-stress. Few studies have evaluated the effects of FLX treatment when chronic stress has induced deleterious effects in patients. Our objective was to evaluate FLX treatment (20 mg/kg/day, i.v.) once these effects are manifested, and the drug's relation to extracellular circulating microRNAs associated with inflammation, a hedonic response (sucrose intake), the forced swim test (FST), and corticosterone levels (CORT) and monoamine concentrations in limbic areas. A group of Wistar rats was divided into groups: Control; FLX; CUMS (for six weeks of exposure to chronic, unpredictable mild stress); and CUMS + FLX, a mixed group. After CUMS, the rats performed the FST, and serum levels of CORT and six microRNAs (miR-16, -21, -144, -155, -146a, -223) were analyzed, as were levels of dopamine, noradrenaline, and serotonin in the prefrontal cortex, hippocampus, and hypothalamus. CUMS reduced body weight, sucrose intake, and hippocampal noradrenaline levels, but increased CORT, immobility behavior on the FST, dopamine concentrations in the prefrontal cortex, and all miRNAs except miR-146a expression. Administering FLX during CUMS reduced CORT levels and immobility behavior on the FST and increased the expression of miR-16, -21, -146a, -223, and dopamine. FLX protects against the deleterious effects of stress by reducing CORT and has an antidepressant effect on the FST, with minimally-modified neurotransmitter levels. FLX increased the expression of miRNAs as part of the antidepressant effect. It also regulates both neuroinflammation and serotoninergic neurotransmission through miRNAs, such as the miR-16.

Hunting for Genes Underlying Emotionality in the Laboratory Rat: Maps, Tools and Traps

Scientists have systematically investigated the hereditary bases of behaviors since the 19th century, moved by either evolutionary questions or clinically-motivated purposes. The pioneer studies on the genetic selection of laboratory animals had already indicated, one hundred years ago, the immense complexity of analyzing behaviors that were influenced by a large number of small-effect genes and an incalculable amount of environmental factors. Merging Mendelian, quantitative and molecular approaches in the 1990s made it possible to map specific rodent behaviors to known chromosome regions. From that point on, Quantitative Trait Locus (QTL) analyses coupled with behavioral and molecular techniques, which involved in vivo isolation of relevant blocks of genes, opened new avenues for gene mapping and characterization. This review examines the QTL strategy applied to the behavioral study of emotionality, with a focus on the laboratory rat. We discuss the challenges, advances and limitations of the search for Quantitative Trait Genes (QTG) playing a role in regulating emotionality. For the past 25 years, we have marched the long journey from emotionality-related behaviors to genes. In this context, our experiences are used to illustrate why and how one should move forward in the molecular understanding of complex psychiatric illnesses. The promise of exploring genetic links between immunological and emotional responses are also discussed. New strategies based on humans, rodents and other animals (such as zebrafish) are also acknowledged, as they are likely to allow substantial progress to be made in the near future.

Selective serotonin reuptake inhibitors: New hope in the fight against COVID-19

The emerging COVID-19 pandemic led to a dramatic increase in global mortality and morbidity rates. As in most infections, fatal complications of coronavirus affliction are triggered by an untrammeled host inflammatory response. Cytokine storms created by high levels of interleukin and other cytokines elucidate the pathology of severe COVID-19. In this respect, repurposing drugs that are already available and might exhibit anti-inflammatory effects have received significant attention. With the in vitro and clinical investigation of several studies on the effect of antidepressants on COVID-19 prognosis, previous data suggest that selective serotonin reuptake inhibitors (SSRIs) might be the new hope for the early treatment of severely afflicted patients. SSRIs' low cost and availability make them potentially eligible for COVID-19 repurposing. This review summarizes current achievements and literature about the connection between SSRIs administration and COVID-19 prognosis.

Selective serotonin reuptake inhibitors and inflammatory bowel disease; Beneficial or malpractice

IBD, a chronic inflammatory disease, has been manifested as a growing health problem. No Crohn's and Colitis councils have officially ratified anti-depressants as a routine regimen for IBD patients. However, some physicians empirically prescribe them to rectify functional bowel consequences such as pain and alleviate psychiatric comorbidities. On the other side, SSRIs' prescription is accompanied by adverse effects such as sleep disturbances. Prolonged intermittent hypoxia throughout sleep disturbance such as sleep apnea provokes periodic reductions in the partial oxygen pressure gradient in the gut lumen. It promotes gut microbiota to dysbiosis, which induces intestinal inflammation. This phenomenon and evidence representing the higher amount of serotonin associated with Crohn's disease challenged our previous knowledge. Can SSRIs worsen the IBD course? Evidence answered the question with the claim on anti-inflammatory properties (central and peripheral) of SSRIs and illuminated the other substantial elements (compared to serotonin elevation) responsible for IBD pathogenesis. However, later clinical evidence was not all in favor of the benefits of SSRIs. Hence, in this review, the molecular mechanisms and clinical evidence are scrutinized and integrated to clarify the interfering molecular mechanism justifying both supporting and disproving clinical evidence. Biphasic dose-dependent serotonin behavior accompanying SSRI shifting function when used up for the long-term can be assumed as the parameters leading to IBD patients' adverse outcomes. Despite more research being needed to elucidate the effect of SSRI consumption in IBD patients, periodic prescriptions of SSRIs at monthly intervals can be recommended.

Microglia Involves in the Immune Inflammatory Response of Poststroke Depression: A Review of Evidence

Poststroke depression (PSD) does not exist before and occurs after the stroke. PSD can appear shortly after the onset of stroke or be observed in the weeks and months after the acute or subacute phase of stroke. The pathogenesis of PSD is unclear, resulting in poor treatment effects. With research advancement, immunoactive cells in the central nervous system, particularly microglia, play a role in the occurrence and development of PSD. Microglia affects the homeostasis of the central nervous system through various factors, leading to the occurrence of depression. The research progress of microglia in PSD has been summarized to review the evidence regarding the pathogenesis and treatment target of PSD in the future.

The Influence of Select Medications on Prospective Hemorrhage Risk in Patients with Spinal or Cerebral Cavernous Malformations

BACKGROUND

Effects of select medications on hemorrhage risk in patients with cerebral or spinal cavernous malformations (CMs) are unknown.

METHODS

From a single-institution prospective cohort of patients with CM (2015-2021), demographics, mode of clinical presentation, and radiographic data were collected. Follow-up was performed with electronic medical record review, in-person visits, and written surveys. Select medication use was ascertained from the time of CM diagnosis to a censor date of first prospective symptomatic hemorrhage, complete surgical excision of sporadic form CM, last follow-up, or death. Using Cox proportional hazards regression model, we assessed effects of antithrombotic agents, fish oil, selective serotonin reuptake inhibitors (SSRIs), vitamin E and D supplementation, statins, and beta blockers on prospective hemorrhage risk.

RESULTS

The study included 364 patients with spinal or cerebral CM (58.0% female; 20.0% familial form; 42.3% presentation to medical attention owing to hemorrhage; 25.8% brainstem location). During a follow-up of 2018 patient-years, 103 prospective hemorrhages occurred. No studied medications increased the prospective CM hemorrhage risk. Antithrombotics, vitamin D supplementation, fish oil, and SSRI were associated with lower hemorrhage risk even after adjusting for age at diagnosis, hemorrhage at diagnosis, and brainstem location.

CONCLUSIONS

Use of select medications with antithrombotic properties do not increase the risk of CM hemorrhage. Vitamin D supplementation, any antithrombotic agent, fish oil, and SSRI were associated with a lower prospective hemorrhage risk. Further studies should evaluate the mechanism of action and potential benefit of these select medications.

Fluoxetine for reducing postoperative cognitive dysfunction in elderly patients after total knee replacement: study protocol for a single-centre, double-blind, randomised, parallel-group, superiority, placebo-controlled trial

INTRODUCTION

Postoperative cognitive dysfunction (POCD) is a common complication following major surgical procedures. The underlying pathophysiology is poorly understood, but the role of neuroinflammation is strongly implicated. Given the antineuroinflammatory and neuroprotective effects of fluoxetine, we hypothesise that fluoxetine may reduce the cumulative incidence of POCD in elderly patients undergoing total knee arthroplasty (TKA).

METHODS AND ANALYSIS

This is a prospective, randomised, double-blind, parallel-group, placebo-controlled, superiority trial. Five hundred elderly patients undergoing unilateral TKA will be randomly assigned to the fluoxetine and placebo groups. The fluoxetine group will receive fluoxetine 20 mg daily 8 weeks preoperatively, and the placebo group will receive placebo capsules daily 8 weeks preoperatively. The primary outcome is the cumulative incidence of POCD at 1 month postoperatively. The secondary outcomes include the occurrence of delirium, the area under the curve of the Numeric Rating Scale pain scores over time, and sleep disturbance. Data on all the results, risk factors and adverse events will also be collected and analysed.

ETHICS AND DISSEMINATION

The Fujian Provincial Hospital Ethics Board has approved the protocol for this trial (identifier number: K2021-01-009). All participants will be required to provide written informed consent before any protocol-specific procedures.

TRIAL REGISTRATION NUMBER

ChiCTR2100050424.

Involvement of Ceramide Metabolism in Cerebral Ischemia

Ischemic stroke, caused by the interruption of blood flow to the brain and subsequent neuronal death, represents one of the main causes of disability in worldwide. Although reperfusion therapies have shown efficacy in a limited number of patients with acute ischemic stroke, neuroprotective drugs and recovery strategies have been widely assessed, but none of them have been successful in clinical practice. Therefore, the search for new therapeutic approaches is still necessary. Sphingolipids consist of a family of lipidic molecules with both structural and cell signaling functions. Regulation of sphingolipid metabolism is crucial for cell fate and homeostasis in the body. Different works have emphasized the implication of its metabolism in different pathologies, such as diabetes, cancer, neurodegeneration, or atherosclerosis. Other studies have shown its implication in the risk of suffering a stroke and its progression. This review will highlight the implications of sphingolipid metabolism enzymes in acute ischemic stroke.

Fluoxetine ameliorates Alzheimer's disease progression and prevents the exacerbation of cardiovascular dysfunction of socially isolated depressed rats through activation of Nrf2/HO-1 and hindering TLR4/NLRP3 inflammasome signaling pathway

Depression is a risk factor for Alzheimer's (AD) and cardiovascular diseases (CVD). Therefore, depression treatment restricts its deteriorating effects on mood, memory and CV system. Fluoxetine is the most widely used antidepressant drug, it has neuroprotective effect through its antioxidant/anti-inflammatory properties. The current study investigated for the first-time the cross link between depression, AD and CVD besides, role of fluoxetine in mitigating such disorders. Depression was induced in rats by social isolation (SI) for 12 weeks, AlCL3 (70 mg/kg/day, i.p.) was used to induce AD which was administered either in SI or normal control (NC) grouped rats starting at 8th week till the end of the experiment, fluoxetine (10 mg/kg/day, p.o) treatment also was started at 8th week. SI and AD showed a statistically significant deteriorated effect on behavioral, neurochemical and histopathological analysis which was exaggerated when two disorder combined than each alone. Fluoxetine treatment showed protective effect against SI, AD and prevents exacerbation of CVD. Fluoxetine improved animals' behavior, increased brain monoamines, BDNF besides increased antioxidant defense mechanism of SOD, TAC contents and increased protein expression of Nrf2/HO-1 with significant decrease of AChE activity, β-amyloid, Tau protein, MDA, TNF-α, IL1β contents as well as decreased protein expression of NF-kB, TLR4, NLRP3 and caspase1. It also showed cardioprotective effects as it improved lipid profile with pronounced decrease of cardiac enzymes of CK-MB, troponin and MEF2. In conclusion, fluoxetine represents as a promising drug against central and peripheral disorders through its anti-inflammatory/antioxidant effects via targeting antioxidant Nrf2/HO-1 and hindering TLR4/NLRP3 inflammasome signaling pathways.

Effect of fluoxetine treatment on neurotoxicity induced by lysolecithin in male rats

Demyelination disorder is an unusual pathologic event, which occurs in the central nervous system (CNS). Multiple sclerosis (MS) is an inflammatory demyelinating disease that affects the CNS, and it is the leading cause of disability in young adults. Lysolecithin (LPC) is one of the best toxin-induced demyelination models. In this study, a suitable model is created, and the effect of fluoxetine treatment is examined on this model. In this case, it was assumed that daily fluoxetine treatment had increased the endogenous remyelination in the LPC model. This study was focused on investigating the influence of the fluoxetine dose of 5 or 10 mg/kg per day for 1 and 4 weeks on LPC-induced neurotoxicity in the corpus callosum region. It was performed as a demyelinating model in male Wistar rats. After 3 days, fluoxetine was injected intraperitoneally (5 or 10 mg/kg per day) for 1 and 4 weeks in each group. After completing the treatment course, the corpus callosum was removed to examine the gene expression and histological analysis was performed. The results of the histopathological study of hematoxylin and eosin staining of the corpus callosum showed that in 1 and 4-week treatment groups, fluoxetine has reduced the level of inflammation at the LPC injection site (5 and 10 mg/kg per day). Fluoxetine treatment in the luxol fast blue (LFB) staining of the corpus callosum has been led to an increase in myelination capacity in all doses and times. The results of the genetic study showed that the fluoxetine has significantly reduced the expression level of tumor necrosis factor-α, nuclear factor κβ, and induced nitric oxide synthase in comparison with the untreated LPC group. Also, the fluoxetine treatment has enhanced the expression level of the forkhead box P3 (FOXP3) gene in comparison with the untreated group. Fluoxetine has increased the expression level of myelination and neurotrophic genes such as myelin basic protein (MBP), oligodendrocyte transcription factor 2 (OLIG2), and brain-derived neurotrophic factor (BDNF). The outcomes demonstrated that fluoxetine reduces inflammation and strengthens the endogenous myelination in the LPC-induced demyelination model; however, supplementary studies are required for specifying the details of its mechanisms.

Acid sphingomyelinase deactivation post-ischemia promotes brain angiogenesis and remodeling by small extracellular vesicles

Antidepressants have been reported to enhance stroke recovery independent of the presence of depressive symptoms. They have recently been proposed to exert their mood-stabilizing actions by inhibition of acid sphingomyelinase (ASM), which catalyzes the hydrolysis of sphingomyelin to ceramide. Their restorative action post-ischemia/reperfusion (I/R) still had to be defined. Mice subjected to middle cerebral artery occlusion or cerebral microvascular endothelial cells exposed to oxygen-glucose deprivation were treated with vehicle or with the chemically and pharmacologically distinct antidepressants amitriptyline, fluoxetine or desipramine. Brain ASM activity significantly increased post-I/R, in line with elevated ceramide levels in microvessels. ASM inhibition by amitriptyline reduced ceramide levels, and increased microvascular length and branching point density in wildtype, but not sphingomyelinase phosphodiesterase-1 ([Smpd1]^-/-) (i.e., ASM-deficient) mice, as assessed by 3D light sheet microscopy. In cell culture, amitriptyline, fluoxetine, and desipramine increased endothelial tube formation, migration, VEGFR2 abundance and VEGF release. This effect was abolished by Smpd1 knockdown. Mechanistically, the promotion of angiogenesis by ASM inhibitors was mediated by small extracellular vesicles (sEVs) released from endothelial cells, which exhibited enhanced uptake in target cells. Proteomic analysis of sEVs revealed that ASM deactivation differentially regulated proteins implicated in protein export, focal adhesion, and extracellular matrix interaction. In vivo, the increased angiogenesis was accompanied by a profound brain remodeling response with increased blood-brain barrier integrity, reduced leukocyte infiltrates and increased neuronal survival. Antidepressive drugs potently boost angiogenesis in an ASM-dependent way. The release of sEVs by ASM inhibitors disclosed an elegant target, via which brain remodeling post-I/R can be amplified.

Fluoxetine-induced hepatic lipid accumulation is mediated by prostaglandin endoperoxide synthase 1 and is linked to elevated 15-deoxy-Δ12,14 PGJ2

Major depressive disorder and other neuropsychiatric disorders are often managed with long-term use of antidepressant medication. Fluoxetine, an SSRI antidepressant, is widely used as a first-line treatment for neuropsychiatric disorders. However, fluoxetine has also been shown to increase the risk of metabolic diseases such as non-alcoholic fatty liver disease. Fluoxetine has been shown to increase hepatic lipid accumulation in vivo and in vitro. In addition, fluoxetine has been shown to alter the production of prostaglandins which have also been implicated in the development of non-alcoholic fatty liver disease. The goal of this study was to assess the effect of fluoxetine exposure on the prostaglandin biosynthetic pathway and lipid accumulation in a hepatic cell line (H4-II-E-C3 cells). Fluoxetine treatment increased mRNA expression of prostaglandin biosynthetic enzymes (Ptgs1, Ptgs2, and Ptgds), PPAR gamma (Pparg), and PPAR gamma downstream targets involved in fatty acid uptake (Cd36, Fatp2, and Fatp5) as well as production of 15-deoxy-Δ^12,14 PGJ₂ a PPAR gamma ligand. The effects of fluoxetine to induce lipid accumulation were attenuated with a PTGS1 specific inhibitor (SC-560), whereas inhibition of PTGS2 had no effect. Moreover, SC-560 attenuated 15-deoxy-Δ^12,14 PGJ₂ production and expression of PPAR gamma downstream target genes. Taken together these results suggest that fluoxetine-induced lipid abnormalities appear to be mediated via PTGS1 and its downstream product 15d-PGJ₂ and suggest a novel therapeutic target to prevent some of the adverse effects of fluoxetine treatment.

Behavioral and histopathological consequences of transient ischemic stroke in the Flinders Sensitive Line rat, a genetic animal model of depression

Patients with depression have an increased risk for stroke, higher mortality rates following stroke and worse functional outcomes among survivors. Preclinical studies may help to better understand the underlying mechanisms linking these two diseases, but only a few animal studies have investigated the effects of prestroke depression. The present study investigates whether Flinders Sensitive Line (FSL) rats, a genetic depression model, respond differently to focal ischemic stroke compared to control strains (Flinders Resistant Line [FRL] and Sprague-Dawley [SD]). Male adult FSL, FRL and SD rats received a unilateral injection of either vehicle or Endothelin-1 (ET-1) adjacent to the middle cerebral artery (MCA). Motor function was assessed at 48 h followed by euthanasia and infarct volume measurement using 2,3,5-triphenyltetrazolium chloride (TTC) staining and image analysis. In a separate cohort behavior was assessed using standard tests for motor function, locomotor activity, cognition, anxiety- and depression-like behavior beginning at 10 days post-injection followed by infarct quantification. We found that ET-1-induced MCA occlusion produced significant infarcts in all three strains. Stroke animals had slightly impaired motor function, but there was no clear interaction effects between strain and stroke surgery on behavioral outcomes. We conclude that FSL rats show no increased susceptibility to brain damage or behavioral deficits following ET-1-induced focal ischemic stroke compared to controls.

Selective serotonin reuptake inhibitors (SSRIs) for stroke recovery

BACKGROUND

Selective serotonin reuptake inhibitors (SSRIs) might theoretically reduce post-stroke disability by direct effects on the brain. This Cochrane Review was first published in 2012 and last updated in 2019.

OBJECTIVES

To determine if SSRIs are more effective than placebo or usual care at improving outcomes in people less than 12 months post-stroke, and to determine whether treatment with SSRIs is associated with adverse effects.

SEARCH METHODS

We searched the Cochrane Stroke Group Trials Register (last searched 7 January 2021), Cochrane Controlled Trials Register (CENTRAL, Issue 7 of 12, 7 January 2021), MEDLINE (1946 to 7 January 2021), Embase (1974 to 7 January 2021), CINAHL (1982 to 7 January 2021), PsycINFO (1985 to 7 January 2021), and AMED (1985 to 7 January 2021). PsycBITE had previously been searched (16 July 2018). We searched clinical trials registers.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) recruiting stroke survivors within the first year. The intervention was any SSRI, at any dose, for any period, and for any indication. The comparator was usual care or placebo. Studies reporting at least one of our primary (disability score or independence) or secondary outcomes (impairments, depression, anxiety, quality of life, fatigue, cognition, healthcare cost, death, adverse events and leaving the study early) were included in the meta-analysis. The primary analysis included studies at low risk of bias.

DATA COLLECTION AND ANALYSIS

We extracted data on demographics, stroke type and, our pre-specified outcomes, and bias sources. Two review authors independently extracted data. We used mean difference (MD) or standardised mean differences (SMDs) for continuous variables, and risk ratios (RRs) for dichotomous variables, with 95% confidence intervals (CIs). We assessed bias risks and applied GRADE criteria.

MAIN RESULTS

We identified 76 eligible studies (13,029 participants); 75 provided data at end of treatment, and of these two provided data at follow-up. Thirty-eight required participants to have depression to enter. The duration, drug, and dose varied. Six studies were at low risk of bias across all domains; all six studies did not need participants to have depression to enter, and all used fluoxetine. Of these six studies, there was little to no difference in disability between groups SMD -0.0; 95% CI -0.05 to 0.05; 5 studies, 5436 participants, high-quality evidence) or in independence (RR 0.98; 95% CI 0.93 to 1.03; 5 studies, 5926 participants; high-quality evidence) at the end of treatment. In the studies at low risk of bias across all domains, SSRIs slightly reduced the average depression score (SMD 0.14 lower, 95% CI 0.19 lower to 0.08 lower; 4 studies; 5356 participants, high-quality evidence) and there was a slight reduction in the proportion with depression (RR 0.75, 95% CI 0.65 to 0.86; 3 studies, 5907 participants, high-quality evidence). Cognition was slightly better in the control group (MD -1.22, 95% CI -2.37 to -0.07; 4 studies, 5373 participants, moderate-quality evidence). Only one study (n = 30) reported neurological deficit score (SMD -0.39, 95% CI -1.12 to 0.33; low-quality evidence). SSRIs resulted in little to no difference in motor deficit (SMD 0.03, -0.02 to 0.08; 6 studies, 5518 participants, moderate-quality evidence). SSRIs slightly increased the proportion leaving the study early (RR 1.57, 95% CI 1.03 to 2.40; 6 studies, 6090 participants, high-quality evidence). SSRIs slightly increased the outcome of a seizure (RR 1.40, 95% CI 1.00 to 1.98; 6 studies, 6080 participants, moderate-quality evidence) and a bone fracture (RR 2.35, 95% CI 1.62 to 3.41; 6 studies, 6080 participants, high-quality evidence). One study at low risk of bias across all domains reported gastrointestinal side effects (RR 1.71, 95% CI 0.33, to 8.83; 1 study, 30 participants). There was no difference in the total number of deaths between SSRI and placebo (RR 1.01, 95% CI 0.82 to 1.24; 6 studies, 6090 participants, moderate quality evidence). SSRIs probably result in little to no difference in fatigue (MD -0.06; 95% CI -1.24 to 1.11; 4 studies, 5524 participants, moderate-quality of evidence), nor in quality of life (MD 0.00; 95% CI -0.02 to 0.02, 3 studies, 5482 participants, high-quality evidence). When all studies, irrespective of risk of bias, were included, SSRIs reduced disability scores but not the proportion independent. There was insufficient data to perform a meta-analysis of outcomes at end of follow-up. Several small ongoing studies are unlikely to alter conclusions.

AUTHORS' CONCLUSIONS

There is high-quality evidence that SSRIs do not make a difference to disability or independence after stroke compared to placebo or usual care, reduced the risk of future depression, increased bone fractures and probably increased seizure risk.

SSRIs: Applications in inflammatory lung disease and implications for COVID-19

Selective serotonin reuptake inhibitors (SSRIs) have anti-inflammatory properties that may have clinical utility in treating severe pulmonary manifestations of COVID-19. SSRIs exert anti-inflammatory effects at three mechanistic levels: (a) inhibition of proinflammatory transcription factor activity, including NF-κB and STAT3; (b) downregulation of lung tissue damage and proinflammatory cell recruitment via inhibition of cytokines, including IL-6, IL-8, TNF-α, and IL-1β; and (c) direct suppression inflammatory cells, including T cells, macrophages, and platelets. These pathways are implicated in the pathogenesis of COVID-19. In this review, we will compare the pathogenesis of lung inflammation in pulmonary diseases including COVID-19, ARDS, and chronic obstructive pulmonary disease (COPD), describe the anti-inflammatory properties of SSRIs, and discuss the applications of SSRIS in treating COVID-19-associated inflammatory lung disease.

Modulation of premotor cortex response to sequence motor learning during escitalopram intake

The contribution of selective serotonin reuptake inhibitors to motor learning by inducing motor cortical plasticity remains controversial given diverse findings from positive preclinical data to negative findings in recent clinical trials. To empirically address this translational disparity, we use functional magnetic resonance imaging in a double-blind, randomized controlled study to assess whether 20 mg escitalopram improves sequence-specific motor performance and modulates cortical motor response in 64 healthy female participants. We found decreased left premotor cortex responses during sequence-specific learning performance comparing single dose and steady escitalopram state. Escitalopram plasma levels negatively correlated with the premotor cortex response. We did not find evidence in support of improved motor performance after a week of escitalopram intake. These findings do not support the conclusion that one week escitalopram intake increases motor performance but could reflect early adaptive plasticity with improved neural processing underlying similar task performance when steady peripheral escitalopram levels are reached.

Microglia Function on Precursor Cells in the Adult Hippocampus and Their Responsiveness to Serotonin Signaling

Microglia are the resident immune cells of the adult brain that become activated in response to pathogen- or damage-associated stimuli. The acute inflammatory response to injury, stress, or infection comprises the release of cytokines and phagocytosis of damaged cells. Accumulating evidence indicates chronic microglia-mediated inflammation in diseases of the central nervous system, most notably neurodegenerative disorders, that is associated with disease progression. To understand microglia function in pathology, knowledge of microglia communication with their surroundings during normal state and the release of neurotrophins and growth factors in order to maintain homeostasis of neural circuits is of importance. Recent evidence shows that microglia interact with serotonin, the neurotransmitter crucially involved in adult neurogenesis, and known for its role in antidepressant action. In this chapter, we illustrate how microglia contribute to neuroplasticity of the hippocampus and interact with local factors, e.g., BDNF, and external stimuli that promote neurogenesis. We summarize the recent findings on the role of various receptors in microglia-mediated neurotransmission and particularly focus on microglia’s response to serotonin signaling. We review microglia function in neuroinflammation and neurodegeneration and discuss their novel role in antidepressant mechanisms. This synopsis sheds light on microglia in healthy brain and pathology that involves serotonin and may be a potential therapeutic model by which microglia play a crucial role in the maintenance of mood.

Is Fluoxetine Good for Subacute Stroke? A Meta-Analysis Evidenced From Randomized Controlled Trials

Background and Purpose: Fluoxetine is a drug commonly used to treat mental disorders, such as depression and obsessive–compulsive disorder, and some studies have shown that fluoxetine can improve motor and function recovery after stroke. Therefore, we performed a meta-analysis to investigate the efficacy and safety of fluoxetine in the treatment of post-stroke neurological recovery.

Methods: PubMed, Embase, and Cochrane Library were searched for randomized controlled trials (RCTs) that were performed to assess the efficacy and safety of fluoxetine for functional and motor recovery in subacute stroke patients up to October 2020. Review Manager 5.3 software was used to assess the data. The risk ratio (RR) and standardized mean difference (SMD) were analyzed and calculated with a fixed effects model.

Results: We pooled 6,788 patients from nine RCTs. The primary endpoint was modified Rankin Scale (mRS). Fluoxetine did not change the proportion of mRS ≤ 2 (P = 0.47). The secondary endpoints were Fugl-Meyer Motor Scale (FMMS), Barthel Index (BI), and National Institutes of Health Stroke Scale (NIHSS). Fluoxetine improved the FMMS (P < 0.00001) and BI(P < 0.0001) and showed a tendency of improving NIHSS (P = 0.08). In addition, we found that fluoxetine reduced the rate of new-onset depression (P < 0.0001) and new antidepressants (P < 0.0001).

Conclusion: In post-stroke treatment, fluoxetine did not improve participants' mRS and NIHSS but improved FMMS and BI. This difference could result from heterogeneities between the trials: different treatment duration, clinical scales sensitivity, patient age, delay of inclusion, and severity of the deficit.

Serotoninergic system targeting in multiple sclerosis: the prospective for pathogenetic therapy

Serotonin (5-hydroxytryptamine) (5-HT) is a neurotransmitter, which mediates neuropsychological functions of the central nervous system (CNS). Recent studies have shown the modulatory effect of 5-HT on gut microbiota functions, which play an essential role in developing CNS inflammatory diseases. Finally, 5-HT is a direct mediator of neuroimmune interaction. The article reviews the literature data on the role of 5-HT in the regulation of neuroinflammation in multiple sclerosis (MS). The influence of 5-HT and selective serotonin reuptake inhibitors (SSRIs) on experimental autoimmune encephalomyelitis (EAE) and MS pathogenesis, as well as the therapeutic potential of serotoninergic drugs as a pathogenetic therapy of MS, are discussed.

Association of SLC6A4 methylation with long-term outcomes after stroke: focus on the interaction with suicidal ideation

Serotonin (5-HT) plays an important role in cerebrovascular homeostasis and psychiatric disorders, including suicidality. Methylation of the serotonin transporter gene (SLC6A4) is associated with 5-HT expression. However, the prognostic roles of SLC6A4 methylation and suicidal ideation (SI) in long-term outcomes of stroke have not been evaluated. We investigated the independent and interactive effects of SLC6A4 methylation and SI immediately after stroke on long-term outcomes. Blood SLC6A4 methylation status and SI based on the suicide item of the Montgomery–Åsberg Depression Rating Scale were assessed in 278 patients at 2 weeks after stroke. After the index stroke, cerebro-cardiovascular events by SLC6A4 methylation status and SI were investigated over an 8–14-year follow-up period and using Cox regression models adjusted for a range of covariates. SLC6A4 hypermethylation and SI within 2 weeks of stroke both predicted worse long-term outcomes, independent of covariates. A significant interaction effect of SI and the methylation status of CpG 4 on long-term stroke outcomes was also identified. The association between SLC6A4 methylation and long-term adverse outcomes may be strengthened in the presence of SI within 2 weeks after stroke. Evaluation of methylation and SI status during the acute phase can be helpful when assessing stroke patients.

Patterns of antidepressant therapy and clinical outcomes among ischaemic stroke survivors

Background and purpose

Depression is common after stroke and is often treated with antidepressant medications (AD). ADs have also been hypothesised to improve stroke recovery, although recent randomised trials were neutral. We investigated the patterns of in-hospital AD initiation after ischaemic stroke and association with clinical and readmission outcomes.

Methods

All Medicare fee-for-service beneficiaries aged 65 or older hospitalised for ischaemic stroke in participating Get With The Guidelines-Stroke hospitals between April and December 2014 were eligible for this analysis. Outcome measures included days alive and not in a healthcare institution (home time), all-cause mortality and readmission within 1-year postdischarge. Propensity score (PS)-adjusted logistic regression models were used to evaluate the associations between AD use and each outcome measure. We also compared outcomes in patients prescribed selective serotonin reuptake inhibitors (SSRIs) AD versus those prescribed non-SSRI ADs.

Results

Of 21 805 AD naïve patients included in this analysis, 1835 (8.4%) were started on an AD at discharge. Patients started on an AD had higher rates of depression and prior ischaemic stroke, presented with higher admission National Institutes of Health Stroke Scale score and were less likely to be discharged home. Similarly, patients started on an SSRI had lower rates of discharge to home. Adjusting for stroke severity, patients started on an AD had worse all-cause mortality, all-cause readmission, major adverse cardiac events, readmission for depression and decreased home-time. However, AD use was also associated with an increased risk for the sepsis, a falsification endpoint, suggesting the presence of residual confounding.

Conclusions

Patients with ischaemic stroke initiated on AD therapy are at increased risk of poor clinical outcomes and readmission even after PS adjustment, suggesting that poststroke depression requiring medication is a poor prognostic sign. Further research is needed to explore the reasons why depression is associated with worse outcome, and whether AD treatment modifies this risk or not.

Electroacupuncture Ameliorates Depressive-Like Behaviors in Poststroke Rats via Activating the tPA/BDNF/TrkB Pathway

BACKGROUND

Electroacupuncture (EA) is a form of physical therapy that has been widely used in clinical practice in China. Post-stroke depression (PSD) is the most common neuropsychiatric complication after stroke. EA has been shown to have beneficial effects on PSD patients. However, the potential mechanism underlying the protective effects of EA on PSD remains unclear. Here, we investigated whether tissue plasminogen activator (tPA)/brain-derived neurotrophic factor (BDNF)/tyrosine kinase receptor B (TrkB) signaling pathway participates in the therapeutic effects of EA in a rat PSD model.

METHODS

Experimental PSD was induced by combining middle cerebral artery occlusion (MCAO) with chronic unpredictable mild stimulation (CUMS) in adult male rats. Bodyweight gain, neurological score, sucrose preference, and open field test were determined at 0, 7, 14, and 35 days after completing MCAO. The protein expressions of tPA, precursor BDNF (proBDNF), mature BDNF (mBDNF), and TrkB were measured by immunofluorescence and Western blot analysis. The tPA inhibitor plasminogen inhibitor-1 (PAI-1) was used to explore whether tPA plays a crucial role in the protective effects of EA on PSD.

RESULTS

Compared with the sham rats, the PSD rats showed decreased bodyweight, deteriorated neurological score, and significant depressive-like behaviors. EA remarkably reversed bodyweight loss, neurological deficit, and depressive-like behaviors in PSD rats. Immunofluorescence staining and Western blot analysis showed that PSD-induced decreased expression of tPA, mBDNF, and TrkB were prevented by EA. Furthermore, we found that the effects of EA against PSD-induced depressive-like behaviors were abolished by PAI-1, the specific inhibitor of tPA.

CONCLUSION

Our results suggest that the improvement in depressive-like behaviors induced by EA is likely achieved via activation of the tPA/BDNF/TrkB pathway.

Preventive Approaches for Post-Stroke Depression: Where Do We Stand? A Systematic Review

PURPOSE

Post-stroke depression (PSD) occurs in one-third of stroke survivors, leading to a substantial decrease in quality of life as well as delayed functional and neurological recovery. Early detection of patients at risk and initiation of tailored preventive measures may reduce the medical and socioeconomic burden associated with PSD. We sought to review the current evidence on pharmacological and non-pharmacological prevention of PSD.

MATERIALS AND METHODS

We conducted a systematic review using PubMed/MEDLINE and bibliographies of identified papers following Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, including randomized controlled studies. Eligible studies were included when performed within 1 year after the index cerebrovascular event. Animal and basic research studies, studies lacking a control group, review papers, and case reports were excluded.

RESULTS

Out of 150 studies screened, 37 met our criteria. Among the strategies identified, administration of antidepressants displayed the most robust evidence for preventing PSD, whereas non-pharmacological interventions such as psychotherapy appear to be the most frequently used approaches to prevent depression after stroke. Research suggests that the efficacy of PSD prevention increases with the duration of preventive treatment. Seven out of 11 studies (63%) that used pharmacological and eight out of 16 (50%) that used non-pharmacological interventions reported a positive preventive effect on PSD.

CONCLUSION

Overall, the current literature on PSD prevention shows heterogeneity, substantiating a need for well-designed randomized controlled trials to test the safety and efficacy of pharmacological as well as non-pharmacological and composite prevention regimens to minimize the risk of PSD in stroke survivors. Integrative strategies combining personalized non-pharmacological interventions such as educational, mental, and physical health support, and pharmacological strategies such as SSRIs may be the most promising approach to prevent PSD.

Tranexamic Acid Improves Memory and Learning Abilities in Aging Mice

Purpose

Although the onset mechanism of Alzheimer’s disease, which co-occurs with aging, has been extensively studied, no effective methods that improve the decline in memory and learning abilities following aging have been developed. Tranexamic acid provided promising results for ameliorating photo-aging and extending the natural lifespan. However, it is unknown whether it affects the decline in memory and learning abilities due to aging. In this study, we examined the effect of tranexamic acid on memory and learning abilities of naturally aging mice.

Methods

ICR mice were orally administered with tranexamic acid (12 mg/kg/day) three times weekly for 2 years, and their memory and learning abilities were compared between the tranexamic acid-treated and non-treated groups.

Results

The decline in memory and learning abilities due to aging was ameliorated by tranexamic acid administration. The expression of plasmin and amyloid-β decreased following the treatment with tranexamic acid. Furthermore, the number of M1-type brain macrophages diminished and that of M2 macrophages increased. In addition, administration of tranexamic acid decreased the concentrations of interleukin (IL)-1β and tumor necrosis factor-α, while it increased the levels of IL-10 and transforming growth factor-α in the brain.

Conclusion

These results indicated that tranexamic acid suppressed the secretion of the inflammatory cytokines aging M1-type macrophages, thereby improving age-related memory and learning abilities.

Safety and efficacy of fluoxetine on functional outcome after acute stroke (AFFINITY): a randomised, double-blind, placebo-controlled trial

BACKGROUND

Trials of fluoxetine for recovery after stroke report conflicting results. The Assessment oF FluoxetINe In sTroke recoverY (AFFINITY) trial aimed to show if daily oral fluoxetine for 6 months after stroke improves functional outcome in an ethnically diverse population.

METHODS

AFFINITY was a randomised, parallel-group, double-blind, placebo-controlled trial done in 43 hospital stroke units in Australia (n=29), New Zealand (four), and Vietnam (ten). Eligible patients were adults (aged ≥18 years) with a clinical diagnosis of acute stroke in the previous 2-15 days, brain imaging consistent with ischaemic or haemorrhagic stroke, and a persisting neurological deficit that produced a modified Rankin Scale (mRS) score of 1 or more. Patients were randomly assigned 1:1 via a web-based system using a minimisation algorithm to once daily, oral fluoxetine 20 mg capsules or matching placebo for 6 months. Patients, carers, investigators, and outcome assessors were masked to the treatment allocation. The primary outcome was functional status, measured by the mRS, at 6 months. The primary analysis was an ordinal logistic regression of the mRS at 6 months, adjusted for minimisation variables. Primary and safety analyses were done according to the patient's treatment allocation. The trial is registered with the Australian New Zealand Clinical Trials Registry, ACTRN12611000774921.

FINDINGS

Between Jan 11, 2013, and June 30, 2019, 1280 patients were recruited in Australia (n=532), New Zealand (n=42), and Vietnam (n=706), of whom 642 were randomly assigned to fluoxetine and 638 were randomly assigned to placebo. Mean duration of trial treatment was 167 days (SD 48·1). At 6 months, mRS data were available in 624 (97%) patients in the fluoxetine group and 632 (99%) in the placebo group. The distribution of mRS categories was similar in the fluoxetine and placebo groups (adjusted common odds ratio 0·94, 95% CI 0·76-1·15; p=0·53). Compared with patients in the placebo group, patients in the fluoxetine group had more falls (20 [3%] vs seven [1%]; p=0·018), bone fractures (19 [3%] vs six [1%]; p=0·014), and epileptic seizures (ten [2%] vs two [<1%]; p=0·038) at 6 months.

INTERPRETATION

Oral fluoxetine 20 mg daily for 6 months after acute stroke did not improve functional outcome and increased the risk of falls, bone fractures, and epileptic seizures. These results do not support the use of fluoxetine to improve functional outcome after stroke.

FUNDING

National Health and Medical Research Council of Australia.

Depressive symptoms after stroke are associated with worse recovery

OBJECTIVE

More studies are needed on how depressive symptoms in stroke patients can impact outcomes. We evaluated the relationship between depression symptom severity and motor outcomes in a cohort of patients with motor impairment from ischemic stroke.

METHOD

We enrolled consecutive ischemic stroke patients without a clinical diagnosis of depression who presented to a single-center urban academic referral hospital. The Patient Health Questionnaire-9 (PHQ-9) scale was used to measure depression symptom severity at three months. Three assessments of motor function were collected at stroke onset and three months: Fugl-Meyer upper extremity (FM-UE), Motricity Index, and Action Research Arm Test (ARAT). We assessed the association between three-month severity on PHQ-9 scores with the outcome measures using univariable and multivariable linear regression models.

RESULTS

Fifty-seven patients (mean age 67.8 ± 17.0 years; 50.9% male; 59.6% Caucasian) were included in the final analysis. Mean (standard deviation) outcome scores at three months were PHQ-9: 6.39 (5), Motricity Index: 86.93 (30.04), FM-UE: 52.67 (17.83), and ARAT: 43.77 (20.03). After adjusting for age, initial National Institute of Health Stroke Scale, and if patient discharged after hospitalization on a selective serotonin reuptake inhibitor, sex, and baseline motor outcome, we found that for every point increase in PHQ-9, the Motricity Index decreased by 0.82 points (p = 0.02) and the FM-UE decreased by 0.77 points (p = 0.049).

CONCLUSION

Depressive symptoms are common in the stroke population. Depressive symptoms after stroke are associated with multiple types of motor impairments. We need better understanding of the biologic and psychologic aspects of depression involved in stroke recovery.

Inflammation-Associated Synaptic Alterations as Shared Threads in Depression and Multiple Sclerosis

In the past years, several theories have been advanced to explain the pathogenesis of Major Depressive Disorder (MDD), a neuropsychiatric disease that causes disability in general population. Several theories have been proposed to define the MDD pathophysiology such as the classic "monoamine-theory" or the "glutamate hypothesis." All these theories have been recently integrated by evidence highlighting inflammation as a pivotal player in developing depressive symptoms. Proinflammatory cytokines have been indeed claimed to contribute to stress-induced mood disturbances and to major depression, indicating a widespread role of classical mediators of inflammation in emotional control. Moreover, during systemic inflammatory diseases, peripherally released cytokines circulate in the blood, reach the brain and cause anxiety, anhedonia, social withdrawal, fatigue, and sleep disturbances. Accordingly, chronic inflammatory disorders, such as the inflammatory autoimmune disease multiple sclerosis (MS), have been associated to higher risk of MDD, in comparison with overall population. Importantly, in both MS patients and in its experimental mouse model, Experimental Autoimmune Encephalomyelitis (EAE), the notion that depressive symptoms are reactive epiphenomenon to the MS pathology has been recently challenged by the evidence of their early manifestation, even before the onset of the disease. Furthermore, in association to such mood disturbance, inflammatory-dependent synaptic dysfunctions in several areas of MS/EAE brain have been observed independently of brain lesions and demyelination. This evidence suggests that a fine interplay between the immune and nervous systems can have a huge impact on several neurological functions, including depressive symptoms, in different pathological conditions. The aim of the present review is to shed light on common traits between MDD and MS, by looking at inflammatory-dependent synaptic alterations associated with depression in both diseases.

Pharmacological Interventions and Rehabilitation Approach for Enhancing Brain Self-repair and Stroke Recovery

Neuroplasticity is a natural process occurring in the brain for the entire life. Stroke is the leading cause of long term disability and a huge medical and financial problem throughout the world. Research conducted over the past decade focused mainly on neuroprotection in the acute phase of stroke while very little studies target the chronic stage. Recovery after stroke depends on the ability of our brain to reestablish the structural and functional organization of neurovascular networks. Combining adjuvant therapies and drugs may enhance the repair processes and restore impaired brain functions. Currently, there are some drugs and rehabilitative strategies that can facilitate brain repair and improve clinical effect even years after stroke onset. Moreover, some of the compounds such as citicoline, fluoxetine, niacin, levodopa, etc. are already in clinical use or are being trialed in clinical issues. Many studies are also testing cell therapies; in our review, we focused on studies where cells have been implemented at the early stage of stroke. Next, we discuss pharmaceutical interventions. In this section, we selected methods of cognitive, behavioral, and physical rehabilitation as well as adjuvant interventions for neuroprotection including noninvasive brain stimulation and extremely low-frequency electromagnetic field. The modern rehabilitation represents a new model of physical interventions with the limited therapeutic window up to six months after stroke. However, previous studies suggest that the time window for stroke recovery is much longer than previously thought. This review attempts to present the progress in neuroprotective strategies, both pharmacological and non-pharmacological that can stimulate the endogenous neuroplasticity in post-stroke patients.

Fluoxetine to improve functional outcomes in patients after acute stroke: the FOCUS RCT

BACKGROUND

Our Cochrane review of selective serotonin inhibitors for stroke recovery indicated that fluoxetine may improve functional recovery, but the trials were small and most were at high risk of bias.

OBJECTIVES

The Fluoxetine Or Control Under Supervision (FOCUS) trial tested the hypothesis that fluoxetine improves recovery after stroke.

DESIGN

The FOCUS trial was a pragmatic, multicentre, parallel-group, individually randomised, placebo-controlled trial.

SETTING

This trial took place in 103 UK hospitals.

PARTICIPANTS

Patients were eligible if they were aged ≥ 18 years, had a clinical stroke diagnosis, with focal neurological deficits, between 2 and 15 days after onset.

INTERVENTIONS

Patients were randomly allocated 20 mg of fluoxetine once per day or the matching placebo for 6 months via a web-based system using a minimisation algorithm.

MAIN OUTCOME MEASURES

The primary outcome was the modified Rankin Scale at 6 months. Patients, carers, health-care staff and the trial team were masked to treatment allocation. Outcome was assessed at 6 and 12 months after randomisation. Patients were analysed by their treatment allocation as specified in a published statistical analysis plan.

RESULTS

Between 10 September 2012 and 31 March 2017, we recruited 3127 patients, 1564 of whom were allocated fluoxetine and 1563 of whom were allocated placebo. The modified Rankin Scale score at 6 months was available for 1553 out of 1564 (99.3%) of those allocated fluoxetine and 1553 out of 1563 (99.4%) of those allocated placebo. The distribution across modified Rankin Scale categories at 6 months was similar in the two groups (common odds ratio adjusted for minimisation variables 0.951, 95% confidence interval 0.839 to 1.079; p = 0.439). Compared with placebo, patients who were allocated fluoxetine were less likely to develop a new episode of depression by 6 months [210 (13.0%) vs. 269 (16.9%), difference -3.78%, 95% confidence interval -1.26% to -6.30%; p = 0.003], but had more bone fractures [45 (2.9%) vs. 23 (1.5%), difference 1.41%, 95% confidence interval 0.38% to 2.43%; p = 0.007]. There were no statistically significant differences in any other recorded events at 6 or 12 months. Health economic analyses showed no differences between groups in health-related quality of life, hospital bed usage or health-care costs.

LIMITATIONS

Some non-adherence to trial medication, lack of face-to-face assessment of neurological status at follow-up and lack of formal psychiatric diagnosis during follow-up.

CONCLUSIONS

20 mg of fluoxetine daily for 6 months after acute stroke did not improve patients' functional outcome but decreased the occurrence of depression and increased the risk of fractures. These data inform decisions about using fluoxetine after stroke to improve functional outcome or to prevent or treat mood disorders. The Assessment oF FluoxetINe In sTroke recoverY (AFFINITY) (Australasia/Vietnam) and Efficacy oF Fluoxetine - a randomisEd Controlled Trial in Stroke (EFFECTS) (Sweden) trials recruited an additional 2780 patients and will report their results in 2020. These three trials have an almost identical protocol, which was collaboratively developed. Our planned individual patient data meta-analysis will provide more precise estimates of the effects of fluoxetine after stroke and indicate whether or not effects vary depending on patients' characteristics and health-care setting.

TRIAL REGISTRATION

Current Controlled Trials ISRCTN83290762.

FUNDING

This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 24, No. 22. See the NIHR Journals Library website for further project information. The Stroke Association (reference TSA 2011101) funded the start-up phase.

Use of Selective Serotonin Reuptake Inhibitors and Outcomes in Stroke Rehabilitation: A Prospective Observational Pilot Cohort Study

Purpose

The aim of this study was to examine the association between selective serotonin reuptake inhibitor (SSRI) therapy and rehabilitation outcomes, specifically disability and quality of life (QOL), in a real-world setting of multi-ethnic Asian patients with first-ever stroke.

Methods

In this prospective observational pilot cohort study, we included patients with first-ever stroke admitted to two inpatient rehabilitation centres in Singapore between January and July 2018. Outcomes were measured using Functional Independence Measure (FIM)-motor scale, modified Barthel Index (MBI) and the Stroke and Aphasia Quality of Life Scale-39 generic (SAQOL-39g) questionnaire. Linear regression was used to assess the association between SSRI therapy and outcomes. Regression coefficients and 95% confidence intervals (CIs) were reported.

Results

Among 57 patients included for analyses, 38.6% received SSRIs. Although SSRI therapy was significantly associated with gains in MBI (coefficient 11.35; 95% CI 0.21–22.50) and SAQOL-39g overall score (coefficient 0.45; 95% CI 0.05–0.85) based on simple linear regression, no significant association between SSRI therapy and any of the investigated outcomes was found after adjustment for confounders. However, an increase in the mean number of physiotherapy and occupational therapy (PT/OT) sessions per day significantly improved FIM-motor (coefficient 16.86; 95% CI 2.64–31.07) and MBI (coefficient 22.79; 95% CI 2.35–43.23) scores.

Conclusion

SSRI therapy did not improve disability and QOL in multi-ethnic Asian patients with first-ever stroke undergoing rehabilitation.

Electronic supplementary material

The online version of this article (10.1007/s40268-019-00287-y) contains supplementary material, which is available to authorized users.

Activation of 5-HT1A postsynaptic receptors by NLX-101 results in functional recovery and an increase in neuroplasticity in mice with brain ischemia

Pharmacological interventions that selectively activate serotonin 5-hydroxytryptramine-1A (5-HT_1A) heteroreceptors may prevent or attenuate the consequences of brain ischemic episodes. The present study investigated whether the preferential 5-HT_1A postsynaptic receptor agonist NLX-101 (a.k.a. F15599) mitigates cognitive and emotional impairments and affects neuroplasticity in mice that are subjected to the bilateral common carotid artery occlusion (BCCAO) model of brain ischemia. The selective serotonin reuptake inhibitor escitalopram (Esc) was used for comparative purposes because it is able to decrease morbidity and improve recovery in stroke patients and ischemic rodents. Sham and BCCAO mice received daily doses of NLX-101 (0.32 mg/kg, i.p) or Esc (20 mg/kg, i.p) for 28 days. During this period, they were evaluated for locomotor activity, anxiety- and despair-related behaviors and hippocampus-dependent cognitive function, using the open field, elevated zero maze, forced swim test and object location test, respectivelly. The mice's brains were processed for biochemical and histological analyses. BCCAO mice exhibited high anxiety and despair-like behaviors and performed worse than controls in the cognitive assessment. BCCAO induced neuronal and dendritic spine loss and decreases in the protein levels of neuronal plasticity markers, including brain-derived neurotrophic factor (BDNF), synaptophysin (SYN), and postsynaptic density protein-95 (PSD-95), in prefrontal cortex (PFC) and hippocampus. NLX-101 and Esc attenuated cognitive impairments and despair-like behaviors in BCCAO mice. Only Esc decreased anxiety-like behaviors due to brain ischemia. Both NLX-101 and Esc blocked the increase in plasma corticosterone levels and, restored BDNF, SYN and PSD-95 protein levels in the hippocampus. Moreover, both compounds impacted positively dentritic remodeling in the hippocampus and PFC of ischemic mice. In the PFC, NLX-101 increased the BDNF protein levels, while Esc in turn, attenuated the decrease in the PSD-95 protein levels induced by BCCAO. The present results suggest that activation of post-synaptic 5-HT_1A receptors is the molecular mechanism for serotonergic protective effects in BCCAO. Moreover, post-synaptic biased agonists such as NLX-101 might constitute promising therapeutics for treatment of functional and neurodegenerative outcomes of brain ischemia.

Effect of fluoxetine on proliferation and/or survival of microglia and oligodendrocyte progenitor cells in the fornix and corpus callosum of the mouse brain

BACKGROUND

Fluoxetine is one of the most widely prescribed antidepressants and a selective inhibitor of presynaptic 5-HT transporters. The fornix is the commissural and projection fiber that transmits signals from the hippocampus to other parts of the brain and opposite site of hippocampus. The corpus callosum (CC) is the largest of the commissural fibers that link the cerebral cortex of the left and right cerebral hemispheres. These brain regions play pivotal roles in cognitive functions, and functional abnormalities in these regions have been implicated in the development of various brain diseases. The purpose of the present study was to investigate the effects of fluoxetine on the proliferation and/or survival of microglia and oligodendrocyte progenitor cells (OPCs) in the fornix and CC, the white matter connecting cortical-limbic system, of the adult mouse brain.

METHODS

The effects of fluoxetine on the proliferation and/or survival of microglia and OPCs were examined in lipopolysaccharide (LPS)-treated and normal mice. Proliferating cells were detected in mice that drank water containing the thymidine analog, bromodeoxyuridine (BrdU), using immunohistochemistry.

RESULT

Fluoxetine significantly attenuated LPS-induced increases in the number of BrdU-labeled microglia and morphological activation from the ramified to ameboid shape, and decreased the number of BrdU-labeled OPCs under basal conditions.

CONCLUSIONS

The present results indicate that fluoxetine exerts inhibitory effects on LPS-induced increases in the proliferation and/or survival and morphological activation of microglia and basal proliferation and/or survival of OPCs in the fornix and CC of adult mice.

Insulin-Like Growth Factor-1 Is Neuroprotective in Aged Rats With Ischemic Stroke

Post-stroke systemic injections of insulin-like growth factor-1 (IGF-1) exert neuroprotective effects in rats. In the current study, we aimed to test the efficacy of IGF-1 neuroprotection in aged rats (24–25 months old) and to compare the results with adult rats (6–7 months old). Furthermore, we addressed putative differences in microglial responses to IGF-1 in adult and aged rats. Rats were subjected to ischemic stroke while they were conscious by infusing endothelin-1 (Et-1) through a guide cannula that was implemented in the vicinity of the middle cerebral artery (MCA). Rats were given subcutaneous injections of IGF-1 (1 mg/kg) at 30 min and 120 min after the insult. Post-stroke IGF-1 treatment reduced the infarct size by 34% and 38% in aged and adult rats, respectively. The IGF-1 treated adult rats also showed significant improvement in sensorimotor function following stroke, while this function was not significantly affected in aged rats. Furthermore, aged rats displayed exaggerated activation of microglia in the ischemic hemisphere. Significant reduction of microglial activation by IGF-1 was only detected at specific regions in the ipsilateral hemisphere of adult rats. We show that IGF-1 reduced infarct size in aged rats with an ischemic stroke. It remains to be established, however, whether the age-related changes in microglial function affect the improvement in behavioral outcomes.

Selective serotonin reuptake inhibitors (SSRIs) for stroke recovery

BACKGROUND

Stroke is a major cause of adult disability. Selective serotonin reuptake inhibitors (SSRIs) have been used for many years to manage depression and other mood disorders after stroke. The 2012 Cochrane Review of SSRIs for stroke recovery demonstrated positive effects on recovery, even in people who were not depressed at randomisation. A large trial of fluoxetine for stroke recovery (fluoxetine versus placebo under supervision) has recently been published, and it is now appropriate to update the evidence.

OBJECTIVES

To determine if SSRIs are more effective than placebo or usual care at improving outcomes in people less than 12 months post-stroke, and to determine whether treatment with SSRIs is associated with adverse effects.

SEARCH METHODS

For this update, we searched the Cochrane Stroke Group Trials Register (last searched 16 July 2018), the Cochrane Controlled Trials Register (CENTRAL, Issue 7 of 12, July 2018), MEDLINE (1946 to July 2018), Embase (1974 to July 2018), CINAHL (1982 July 2018), PsycINFO (1985 to July 2018), AMED (1985 to July 2018), and PsycBITE March 2012 to July 2018). We also searched grey literature and clinical trials registers.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) that recruited ischaemic or haemorrhagic stroke survivors at any time within the first year. The intervention was any SSRI, given at any dose, for any period, and for any indication. We excluded drugs with mixed pharmacological effects. The comparator was usual care or placebo. To be included, trials had to collect data on at least one of our primary (disability score or independence) or secondary outcomes (impairments, depression, anxiety, quality of life, fatigue, healthcare cost, death, adverse events and leaving the trial early).

DATA COLLECTION AND ANALYSIS

We extracted data on demographics, type of stroke, time since stroke, our primary and secondary outcomes, and sources of bias. Two review authors independently extracted data from each trial. We used standardised mean differences (SMDs) to estimate treatment effects for continuous variables, and risk ratios (RRs) for dichotomous effects, with their 95% confidence intervals (CIs). We assessed risks of bias and applied GRADE criteria.

MAIN RESULTS

We identified a total of 63 eligible trials recruiting 9168 participants, most of which provided data only at end of treatment and not at follow-up. There was a wide age range. About half the trials required participants to have depression to enter the trial. The duration, drug, and dose varied between trials. Only three of the included trials were at low risk of bias across the key 'Risk of bias' domains. A meta-analysis of these three trials found little or no effect of SSRI on either disability score: SMD -0.01 (95% CI -0.09 to 0.06; P = 0.75; 2 studies, 2829 participants; moderate-quality evidence) or independence: RR 1.00 (95% CI 0.91 to 1.09; P = 0.99; 3 studies, 3249 participants; moderate-quality evidence). We downgraded both these outcomes for imprecision. SSRIs reduced the average depression score (SMD 0.11 lower, 0.19 lower to 0.04 lower; 2 trials, 2861 participants; moderate-quality evidence), but there was a higher observed number of gastrointestinal side effects among participants treated with SSRIs compared to placebo (RR 2.19, 95% CI 1.00 to 4.76; P = 0.05; 2 studies, 148 participants; moderate-quality evidence), with no evidence of heterogeneity (I2 = 0%). For seizures there was no evidence of a substantial difference. When we included all trials in a sensitivity analysis, irrespective of risk of bias, SSRIs appeared to reduce disability scores but not dependence. One large trial (FOCUS) dominated the results. We identified several ongoing trials, including two large trials that together will recruit more than 3000 participants.

AUTHORS' CONCLUSIONS

We found no reliable evidence that SSRIs should be used routinely to promote recovery after stroke. Meta-analysis of the trials at low risk of bias indicate that SSRIs do not improve recovery from stroke. We identified potential improvements in disability only in the analyses which included trials at high risk of bias. A further meta-analysis of large ongoing trials will be required to determine the generalisability of these findings.

TLR4 signaling modulation of PGC1-α mediated mitochondrial biogenesis in the LPS-Chronic mild stress model: Effect of fluoxetine and pentoxiyfylline

AIM

The addition of repeated lipopolysaccharide (LPS) to chronic mild stress was recently proposed in our lab as an alternative model of depression, highlighting the possible interaction between stress and immune-inflammatory pathways in predisposing depression. Given that CMS-induced depressive behavior was previously related to impaired hippocampal energy metabolism and mitochondrial dysfunction, our current study aimed to investigate the interplay between toll-like receptor 4 (TLR4) signaling and peroxisome proliferator-activated receptor gamma coactivators-1-alpha (PGC1-α) as a physiological regulator of energy metabolism and mitochondrial biogenesis in the combined LPS/CMS model.

MAIN METHODS

Male Wistar rats were exposed to either LPS (50 μg/kg i.p.) over 2 weeks, CMS protocol for 4 weeks or LPS over 2 weeks followed by 4 weeks of CMS (LPS/CMS). Three additional groups of rats were exposed to LPS/CMS protocol and treated with either pentoxifylline (PTX), fluoxetine (FLX) or a combination of both. Rats were examined for behavioral, neurochemical, gene expression and mitochondrial ultra-structural changes.

KEY FINDINGS

LPS/CMS increased the expression of TLR4 and its downstream players; MyD88, NFκB and TNF-α along with an escalation in hippocampal-energy metabolism and p-AMPK. Simultaneously LPS/CMS attenuated the expression of PGC1-α/NRF1/Tfam and mt-DNA. The antidepressant (AD) 'FLX', the TNF-α inhibitor 'PTX' and their combination ameliorated the LPS/CMS-induced changes. Interestingly, all the aforementioned changes induced by the LPS/CMS combined model were significantly less than those induced by CMS alone.

SIGNIFICANCE

Blocking the TLR4/NFκB signaling enhanced the activation of the PGC1-α/NRF1/Tfam and mt-DNA content independent on the activation of the energy-sensing kinase AMPK.